Printing device of modulation on faceplate of cathode-ray tube

ABSTRACT

AN ELCTRONIC PRINTING DEVICE IN WHICH A CATHODE RAY TUBE IS UTILIZED AS AN ELECTRON SOURCE FOR ELECTRIFYING THE PRINTING INK BUT THE MODULATION OF INK DEPOSITION BY THE INFORMATION SIGNAL IS PERFORMED OUTSIDE OF THE CATHODE RAY TUBE AND AT A LOW POTENTIAL LEVEL AND THE PRINTING IS DONE DIRECTLY ON A SHEET OF ORDINARY PAPER.

1971 Eucm MIYAZAKI 355371?" PRINTING DEYICE OF MODULATION ON FACEPLATE OI CATHODE-RAY TUBE Filed Dec. 12, 1968 2 Sheets-Sheet 1 INVENTOR EIICH/ M1 yfimK/ ATTORNEYS Jan.5, 1971 EHCHI MIY A Z AKI v 3553,719-

PRINTING DEVICE OF MODULATION 0N FACEPLATE OF CATHODE-RAY TUBE Filed Dec, 12 1968 2 Sheets-Shet 2 INVENTOR EnaH/ Any/92pm ATTORNEYS United States Patent O 3,553,719 PRINTING DEVICE OF MODULATION ON FACEPLATE OF CATHODE-RAY TUBE Eiichi Miyazaki, Tokyo, Japan, assignor to Matsushita Electric Industrial Co., Ltd., Osaka, Japan, a corporation of Japan Filed Dec. 12, 1968, Ser. No. 783,210 Claims priority, application Japan, Dec. 18, 1967, 42/82,482; Dec. 28, 1967, 43/87, 43/132 Int. Cl. G01d 15/16 US. Cl. 346-140 4 Claims ABSTRACT OF THE DISCLOSURE An electronic printing device in which a cathode ray tube is utilized as an electron source for electrifying the printing ink but the modulation of ink deposition by the information signal is performed outside of the cathode ray tube and at a low potential level and the printing is done directly on a sheet of ordinary paper.

This invention relates to an electronic printing device, particularly to such a device in which the modulation of the inking with the information signal is performed outside of the cathode ray tube which supplies a high potential electric charge.

A conventional system for electrostatically recording an optical image comprises an electrostatic recording tube in which the information signal voltage is applied to a grid of the electron gun to modulate said beam, the modulated beam being deflected by a deflecting coil to scan the array of the pins, the electric charge received by a pin being further transferred to a recording medium placed in front of the face of the recording tube. The latent image on the recording medium may be developed by an appropriate developing agent such as a toner. Such a system inevitably has disadvantages in that the image signal must be applied to a high potential electrode and therefore the signal amplifier per se must be maintained at a high negative potential level, thus making the constitution of the system and the operation complicated and diflicult.

Another conventional system for electrostatically recording an optical image utilizes a layer of photoconductive material applied to the surface of a dielectric substrate, the surface of said photoconductive layer being uniformly charged with electricity and then being exposed to the luminous signal to discharge the electricity at the spots where said layer has become conductive as a result of exposure to the luminous signal and thereby to produce an electrostatic latent image. In this conventional method, the recording medium on which the image is reproduced is the photoconductive layer applied on an insulating sheet as mentioned above, and ordinary paper cannot be used as recording medium.

The above-mentioned disadvantages of the covnentional methods are eliminated by this invention.

According to this invention, there is provided a printing device of modulation on face-plate of ORT which comprises a cathode ray tube, an ink vessel disposed in front of said cathode ray tube so that the ink in said vessel is electrified by an electron beam from said cathode ray tube, a control electrode disposed outside of said cathode ray tube to modulate the electrification of said ink according ot the information signal voltage which is applied to said electrode, and means for depositing said ink on a recording medium which may be a sheet of ordinary paper.

The objects and features of this invention will be clarified in the following description of embodiments of this invention, which is made with reference to the accompanying drawings, in which;

3,553,719 Patented Jan. 5, 1971 FIG. 1 is a sectioned elevation of an embodiment of this invention; I

FIG. 2 is a sectioned plan view of the same embodiment;

FIG. 3 is a sectioned elevation of another embodiment of this invention; and

FIG. 4 is a sectioned plan view of still another embodiment of this invention.

According to the embodiment shown in FIGS. 1 and 2, the printing device of this invention comprises an electron-pervious thin film type printing tube, an ink vessel disposed in front of the thin film of said tube with a space of several tens microns between them, said vessel having small holes in the portion opposite to said thin film, and a control electrode interposed between insulating paltes and disposed in front of said small holes, thereby the ink in said vessel being electrified by the accelerated electron beam from said printing tube, the amount of electrification of the ink being modulated according to the potential of said control electrode, and thus the amount of the ink deposited on the recording paper being controlled by said potential which depends on the information signal.

Referring to FIGS. 1 and 2, an electron beam projected from the electron gun 2 of a cathode ray tube 1 is deflected by a deflecting coil 3 for scanning. The deflected electron beam passes through an electron-pervious thin film 4 made of, for example, aluminum foil. Quick-drying ink 6 of a dielectric nature received in an ink vessel 5 of dielectric material disposed in front of the above-mentioned thin film 4, is electrified by the negative charge of the electron beam which passed the thin film. The negative electric charge carried on the ink 6 is acted on by thesignal voltage impressed on an electrode 8 interposed between insulating plates 7, and ink in an amount according to said signal voltage is drawn out by a background electrode 9 and is transferred to the recording paper which may be a sheet of ordinary paper. Thus, the recording is completed.

The other components shown in the figures are an electron accelerating voltage source 11 for the cathode ray tube, a bias voltage source 12, a voltage source 13 for impressing the ink accelerating voltage on the background electrode 9, and the signal source 14.

With reference to FIG. 1 as an example, it should be noted that electrode 8 is a ring electrode which functions to increase and decrease the amount of the ink particles in the manner of an electron beam in a triode.

The electron accelerating voltage source 11 is connected between the electron gun 2 and one end of a secondary electron emissive material 15 through the bias voltage source 12 to establish a beam accelerating field therebetween. The bias voltage source 12 is connected between one end of the electrode 8 and said end of the material 15 through the signal source 14 to establish another field therebetween, and the voltage source 13 is connected between said end of the material 15 and the background electrode 9 to constitute therebetween a field for accelerating charged ink particles.

Further, if a secondary electron emissive material 15 such as gold is applied to the thin film 4, a great number of secondary electrons will be emitted from said material 15 when the electron beam passed through the thin film 4 hits said material 15. The ink is electrified with the thus emitted abundant secondary electrons and the electrified ink is controlled with the voltage of the electrode 8 as described above. Thus, the recording is carried out more effectively.

As described above, according to this invention, information in the form of an electric signal can be printed directly on a sheet of ordinary paper only by applying the electric signal to the modifying electrode which is at ground potential. Further, since the electron beam is led to the outside of the cathode ray tube, the multiplying effect of secondary electron emission can be utilized, which further improves the recording sensitivity of the device.

FIG. 3 shows another embodiment of this invention, in which an electrostatic printing tube is utilized as the source of an electric charge for electrifying the printing ink, and the ink is transferred to a sheet of ordinary paper by an amount corresponding to the signal voltage. In short, this embodiment of this invention comprises an electrostatic printing tube which has an array of pins in the face plate, an ink vessel disposed in front of the face plate of the printing tube with a'space of several tens microns between them, said vessel having small holes in opposed relation to said pins of said printing tube, and a control electrode interposed between insulating plates.

Referring to FIG. 3, an electron beam projected from the electron gun 17 of an electrostatic printing tube 16 and deflected by a deflecting coil 18 electrifies a pin 19 which transfers the electric charge to the quick-drying ink 21 received in an ink vessel 20 of dielectric material. The electric charge carried on the ink 21 is acted on by the signal voltage impressed on a modifying or controlling electrode 22 interposed between insulating plates 25, and the ink in an amount according to said signal voltage is drawn out by a background electrode 23 and is transferred to the recording medium 24 which is usually a sheet of ordinary paper. Thus, the printing is completed.

The other components shown in FIG. 3 are an electron accelerating voltage source 26 for the printing tube, a bias voltage source 27, a voltage source 28 for impressing the ink accelerating voltage on the background electrode 23, and the signal source 29.

As described above, according to this embodiment of the present invention too, information received in the form of an electric signal can be recorded directly on a sheet of ordinary paper only by applying the electric signal to the modifying electrode which is at a low potential.

FIG. 4 shows still another embodiment of this invention, in which a fibre-optics cathode ray tube is utilized as the source of an electric charge to be imparted to the printing ink; that is, the potential of photoconductive layer disposed in front of said tube is varied according to the signal voltage and the ink disposed adjacently to said layer is electrified correspondingly. Control of the amount of ink and printing on ordinary paper are performed in the same manner as in the above-described two embodiments.

Referring to FIG. 4, an electron beam projected from the electron gun 32 of a fibre-optics cathode ray tube 31 and deflected by a deflecting coil 42, hits the electroluminescent layer 33 applied to the inner face of said cathode ray tube and causes the hit spot of said layer to luminesce. This luminescent light is transmitted through the face 34 of the tube and is projected to the photoconductive layer 36, whose resistivity decreases accordingly, thereby producing an electric charge. The produced electric charge is transferred to the ink 37 of di electric nature disposed in front of the photoconductive layer 36 by the voltage impressed between said layer 36 and an electrode 40 interposed between insulating plates 41, and the electrified ink is drawn out according to the signal voltage and carried to the paper 38 being attracted by background electrode 39. The other components shown in FIG. 4 are the signal source 35, an electron accelerating voltage source 43, a voltage source 44 for producing electric change in the irradiated photoconductive layer 36, and a voltage source 45 for attracting the electrified ink toward the recording paper 38.

As described above, according to this embodiment of the present invention, a picture information received in the form of an electric signal can be recorded directly on ordinary paper by attaching only a simple apparatus to a fibre-optics cathode ray tube, the modulation by the information signal being performed outside of the tube but not at a high potential electrode of the tube.

What I claim is:

1. A printing device comprising a cathode ray tube having a face plate, an ink vessel disposed in front of said cathode ray tube, a means for electrifying the ink in said vessel by the electron beam of said cathode ray tube, a control electrode disposed adjacent said ink vessel between the face plate and the recording medium to modulate the amount of electrification of said ink according to the information signal voltage which is applied to said electrode, and means for depositing said ink on a recording medium.

2. The printing device of claim 1, wherein said means for electrifying is an electron pervious thin film disposed in said face plate, said ink vessel having small holes, opposite said film.

3. The printing device of claim 1, wherein said means for electrifying is an array of pins disposed on said face plate, said ink vessel having small holes opposite said 131115.

4. The printing device of claim 1, wherein said means for electrifying is a photoconductive layer 36 disposed in front of said face plate and said cathode ray tube has fiber optics disposed in said face plate.

References Cited UNITED STATES PATENTS 2,771,336 11/1956 MacGriff 346-74 2,894,799 7/1959 McCreary 346-74 3,341,859 9/1967 Adams 346140 3,484,793 12/1969 Weigl 346--75 JOSEPH W. HARTARY, Primary Examiner US. Cl. X.R. 

